1. Field of the Invention
The invention relates to a wheel of the spoked bicycle wheel type and the hub with which said wheel can be equipped.
The invention applies to bicycle wheels or to any means of locomotion comprising wheels with spokes.
2. Description of the Related Art
Conventionally, a bicycle wheel comprises a rim, a hub with an axle corresponding to the axle of the wheel, as well as an arrangement of spokes allowing the rim to be connected to the hub, the spokes being fixed at one of their ends to the left and right flanges (or edges) of the hub and at the other end to the inner perimeter of the rim. The spokes make it possible to confer rigidity to the wheel and to transmit the torque exerted on the axle when the cyclist is pedaling. The arrangement of the spokes is conventionally the same on each flange of the hub, but it can be different, particularly for the rear wheel. It is in fact known today, to improve performance, for example for racing bicycles, that the rear wheel comprises a different arrangement of spokes on each flange of the hub.
There exist today two types of spoke arrangements, a so-called radial spoking and a so-called tangential spoking.
In radial spoking, the spokes are arranged perpendicular to the axle toward the rim. And no spoke crosses another. The advantage of radial spoking is simplicity of assembly and especially weight saving because the spokes are shorter. But the wheel is less comfortable because impacts are transmitted radially. This spoking is found only on the front, non-driving wheels, and with braking at the rim. Radial spoking is not used on a rear wheel, because the pedaling torque would shear the spoke at its head.
In tangential spoking, the spokes extend tangentially to the hub, some to the left, some to the right, and do cross over one another. With tangential spoking, power is transmitted by one-half of the spokes.
Thus radial spoking, with spokes not crossing and perpendicular to the hub, makes it possible to obtain a very light (little matter) and vertically very rigid wheel, to the detriment of comfort and flexibility.
To effectively transmit torque from the hub to the rim, however, as is the case with driving wheels or wheels with disk or drum brakes, it is necessary, for better longevity, to have an inclined arrangement of spokes on the flanges of the hub. This allows better torque capacity (but minimal vertical rigidity).
To improve the performance of bicycles, manufacturers have made bicycles lighter by using materials that are mechanically very strong and at the same time lightweight for manufacturing frames. It is more and more common today to find bicycles made of light alloys such as aluminum alloys or titanium alloys, or carbon fibers.
With the aim of always improving the performance of bicycles, it is also known to lighten bicycles still further by equipping them with rims made of light alloys, aluminum or titanium alloys, or of carbon composite material.